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Comparing cvsroot/Coro/Coro.pm (file contents):
Revision 1.9 by root, Sun Jul 15 02:35:52 2001 UTC vs.
Revision 1.30 by root, Sat Aug 11 19:59:19 2001 UTC

… …
14 14
15 sub some_func : Coro { 15 sub some_func : Coro {
16 # some more async code 16 # some more async code
17 } 17 }
18 18
19 yield; 19 cede;
20 20
21=head1 DESCRIPTION 21=head1 DESCRIPTION
22 22
23This module collection manages coroutines. Coroutines are similar to
24Threads but don't run in parallel.
25
26This module is still experimental, see the BUGS section below.
27
28In this module, coroutines are defined as "callchain + lexical variables
29+ @_ + $_ + $@ + $^W + C stack), that is, a coroutine has it's own
30callchain, it's own set of lexicals and it's own set of perl's most
31important global variables.
32
23=cut 33=cut
24 34
25package Coro; 35package Coro;
26 36
27use Coro::State; 37use Coro::State;
28 38
29use base Exporter; 39use base Exporter;
30 40
31$VERSION = 0.04; 41$VERSION = 0.45;
32 42
33@EXPORT = qw(async yield schedule); 43@EXPORT = qw(async cede schedule terminate current);
34@EXPORT_OK = qw($current); 44@EXPORT_OK = qw($current);
35 45
36{ 46{
37 use subs 'async';
38
39 my @async; 47 my @async;
48 my $init;
40 49
41 # this way of handling attributes simply is NOT scalable ;() 50 # this way of handling attributes simply is NOT scalable ;()
42 sub import { 51 sub import {
43 Coro->export_to_level(1, @_); 52 Coro->export_to_level(1, @_);
44 my $old = *{(caller)[0]."::MODIFY_CODE_ATTRIBUTES"}{CODE}; 53 my $old = *{(caller)[0]."::MODIFY_CODE_ATTRIBUTES"}{CODE};
… …
46 my ($package, $ref) = (shift, shift); 55 my ($package, $ref) = (shift, shift);
47 my @attrs; 56 my @attrs;
48 for (@_) { 57 for (@_) {
49 if ($_ eq "Coro") { 58 if ($_ eq "Coro") {
50 push @async, $ref; 59 push @async, $ref;
60 unless ($init++) {
61 eval q{
62 sub INIT {
63 &async(pop @async) while @async;
64 }
65 };
66 }
51 } else { 67 } else {
52 push @attrs, @_; 68 push @attrs, $_;
53 } 69 }
54 } 70 }
55 return $old ? $old->($package, $name, @attrs) : @attrs; 71 return $old ? $old->($package, $ref, @attrs) : @attrs;
56 }; 72 };
57 } 73 }
58 74
59 sub INIT {
60 async pop @async while @async;
61 }
62} 75}
63 76
64=item $main 77=item $main
65 78
66This coroutine represents the main program. 79This coroutine represents the main program.
67 80
68=cut 81=cut
69 82
70our $main = new Coro; 83our $main = new Coro;
71 84
72=item $current 85=item $current (or as function: current)
73 86
74The current coroutine (the last coroutine switched to). The initial value is C<$main> (of course). 87The current coroutine (the last coroutine switched to). The initial value is C<$main> (of course).
75 88
76=cut 89=cut
77 90
… …
79if ($current) { 92if ($current) {
80 $main->{specific} = $current->{specific}; 93 $main->{specific} = $current->{specific};
81} 94}
82 95
83our $current = $main; 96our $current = $main;
97
98sub current() { $current }
84 99
85=item $idle 100=item $idle
86 101
87The coroutine to switch to when no other coroutine is running. The default 102The coroutine to switch to when no other coroutine is running. The default
88implementation prints "FATAL: deadlock detected" and exits. 103implementation prints "FATAL: deadlock detected" and exits.
… …
93our $idle = new Coro sub { 108our $idle = new Coro sub {
94 print STDERR "FATAL: deadlock detected\n"; 109 print STDERR "FATAL: deadlock detected\n";
95 exit(51); 110 exit(51);
96}; 111};
97 112
98# we really need priorities... 113# this coroutine is necessary because a coroutine
99my @ready = (); # the ready queue. hehe, rather broken ;) 114# cannot destroy itself.
115my @destroy;
116my $manager = new Coro sub {
117 while() {
118 delete ((pop @destroy)->{_coro_state}) while @destroy;
119 &schedule;
120 }
121};
100 122
101# static methods. not really. 123# static methods. not really.
102 124
103=head2 STATIC METHODS 125=head2 STATIC METHODS
104 126
105Static methods are actually functions that operate on the current process only. 127Static methods are actually functions that operate on the current process only.
106 128
107=over 4 129=over 4
108 130
109=item async { ... }; 131=item async { ... } [@args...]
110 132
111Create a new asynchronous process and return it's process object 133Create a new asynchronous process and return it's process object
112(usually unused). When the sub returns the new process is automatically 134(usually unused). When the sub returns the new process is automatically
113terminated. 135terminated.
114 136
115=cut 137 # create a new coroutine that just prints its arguments
138 async {
139 print "@_\n";
140 } 1,2,3,4;
116 141
142The coderef you submit MUST NOT be a closure that refers to variables
143in an outer scope. This does NOT work. Pass arguments into it instead.
144
145=cut
146
117sub async(&) { 147sub async(&@) {
118 (new Coro $_[0])->ready; 148 my $pid = new Coro @_;
149 $manager->ready; # this ensures that the stack is cloned from the manager
150 $pid->ready;
151 $pid;
119} 152}
120 153
121=item schedule 154=item schedule
122 155
123Calls the scheduler. Please note that the current process will not be put 156Calls the scheduler. Please note that the current process will not be put
124into the ready queue, so calling this function usually means you will 157into the ready queue, so calling this function usually means you will
125never be called again. 158never be called again.
126 159
127=cut 160=cut
128 161
129my $prev;
130
131sub schedule {
132 # should be done using priorities :(
133 ($prev, $current) = ($current, shift @ready || $idle);
134 Coro::State::transfer($prev, $current);
135}
136
137=item yield 162=item cede
138 163
139Yield to other processes. This function puts the current process into the 164"Cede" to other processes. This function puts the current process into the
140ready queue and calls C<schedule>. 165ready queue and calls C<schedule>, which has the effect of giving up the
166current "timeslice" to other coroutines of the same or higher priority.
141 167
142=cut 168=cut
143 169
144sub yield { 170=item terminate
171
172Terminates the current process.
173
174Future versions of this function will allow result arguments.
175
176=cut
177
178sub terminate {
145 $current->ready; 179 $current->cancel;
146 &schedule; 180 &schedule;
147} 181 die; # NORETURN
148
149=item terminate
150
151Terminates the current process.
152
153=cut
154
155sub terminate {
156 &schedule;
157} 182}
158 183
159=back 184=back
160 185
161# dynamic methods 186# dynamic methods
… …
164 189
165These are the methods you can call on process objects. 190These are the methods you can call on process objects.
166 191
167=over 4 192=over 4
168 193
169=item new Coro \&sub; 194=item new Coro \&sub [, @args...]
170 195
171Create a new process and return it. When the sub returns the process 196Create a new process and return it. When the sub returns the process
172automatically terminates. To start the process you must first put it into 197automatically terminates. To start the process you must first put it into
173the ready queue by calling the ready method. 198the ready queue by calling the ready method.
174 199
200The coderef you submit MUST NOT be a closure that refers to variables
201in an outer scope. This does NOT work. Pass arguments into it instead.
202
175=cut 203=cut
204
205sub _newcoro {
206 terminate &{+shift};
207}
176 208
177sub new { 209sub new {
178 my $class = shift; 210 my $class = shift;
179 my $proc = $_[0];
180 bless { 211 bless {
181 _coro_state => new Coro::State ($proc ? sub { &$proc; &terminate } : $proc), 212 _coro_state => (new Coro::State $_[0] && \&_newcoro, @_),
182 }, $class; 213 }, $class;
183} 214}
184 215
185=item $process->ready 216=item $process->ready
186 217
187Put the current process into the ready queue. 218Put the current process into the ready queue.
188 219
189=cut 220=cut
190 221
191sub ready { 222=item $process->cancel
223
224Like C<terminate>, but terminates the specified process instead.
225
226=cut
227
228sub cancel {
192 push @ready, $_[0]; 229 push @destroy, $_[0];
230 $manager->ready;
193} 231}
194 232
195=back 233=back
196 234
197=cut 235=cut
198 236
1991; 2371;
200 238
239=head1 BUGS/LIMITATIONS
240
241 - could be faster, especially when the core would introduce special
242 support for coroutines (like it does for threads).
243 - there is still a memleak on coroutine termination that I could not
244 identify. Could be as small as a single SV.
245 - this module is not well-tested.
246 - if variables or arguments "disappear" (become undef) or become
247 corrupted please contact the author so he cen iron out the
248 remaining bugs.
249 - this module is not thread-safe. You must only ever use this module from
250 the same thread (this requirement might be loosened in the future to
251 allow per-thread schedulers, but Coro::State does not yet allow this).
252
201=head1 SEE ALSO 253=head1 SEE ALSO
202 254
203L<Coro::Channel>, L<Coro::Cont>, L<Coro::Specific>, L<Coro::Semaphore>, 255L<Coro::Channel>, L<Coro::Cont>, L<Coro::Specific>, L<Coro::Semaphore>,
204L<Coro::Signal>, L<Coro::State>. 256L<Coro::Signal>, L<Coro::State>, L<Coro::Event>, L<Coro::RWLock>,
257L<Coro::Handle>, L<Coro::Socket>.
205 258
206=head1 AUTHOR 259=head1 AUTHOR
207 260
208 Marc Lehmann <pcg@goof.com> 261 Marc Lehmann <pcg@goof.com>
209 http://www.goof.com/pcg/marc/ 262 http://www.goof.com/pcg/marc/

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